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    SubjectRe: [PATCH 10/11] x86: Remove unnecessary ifdefs from i387 code.
      Hi Brian,

    On 8/30/10 2:38 AM, Brian Gerst wrote:
    > On Sun, Aug 29, 2010 at 3:00 PM, Pekka Enberg<penberg@kernel.org> wrote:
    >> On Sat, Aug 28, 2010 at 7:04 PM, Brian Gerst<brgerst@gmail.com> wrote:
    >>> Remove ifdefs for code that the compiler can optimize away on 64-bit.
    >>>
    >>> Signed-off-by: Brian Gerst<brgerst@gmail.com>
    >>> @@ -74,10 +74,8 @@ static void __cpuinit init_thread_xstate(void)
    >>>
    >>> if (cpu_has_fxsr)
    >>> xstate_size = sizeof(struct i387_fxsave_struct);
    >>> -#ifdef CONFIG_X86_32
    >>> else
    >>> xstate_size = sizeof(struct i387_fsave_struct);
    >>> -#endif
    >>> }
    >> I guess this is OK but keep in mind that cpu_has_fsxr is _not_
    >> optimized by the compiler on 64-bit so the change probably increases
    >> kernel text by few bytes.
    > FXSR is a required feature on 64-bit, therefore cpu_has_fxsr is always true.
    Yes, I realize that but it will still read boot_cpu_data at runtime, no?

    Pekka


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